T 0949/13 - Taxol

Key points

• This Euro-PCT application has an international filing date 26.01.1994 (!). The patent was published in October 2010. The decision of the opposition division to maintain the patent was taken in 2013. The decision of the Board was taken on 19.12.2019 and was issued in writing on 29.07.2020.
• Some features of claim 1 of the main request were taken from the description after grant and the Board decides that these are unclear. 
• " the opposition division's and the [patentee's] interpretation is not the only way of construing the aforementioned feature. In the board's view, another equally valid and technically feasible understanding of feature iii) is "
• " It follows from the above that feature iii) is not only broad, as argued by the opposition division, but also ambiguous as it can be understood in various ways, i.e. as referring to the point of delivery of the therapeutic agent or to the form in which the therapeutic agent is delivered. This leaves the public in doubt as to what subject-matter is covered and not covered by claim 1 of the main request."
• The patent is revoked. 

EPO T 0949/13 - link





3. Clarity (Article 84 EPC)

3.1 The sole claim of the main request is directed to the use of taxol for the preparation of a medicament for inhibiting one or more pathological activities of normal mammalian vascular smooth muscle cells for a sufficient period of time to maintain an expanded vessel luminal area. Taxol is identified as a cytoskeletal inhibitor and characterised as a cytostatic therapeutic agent. It is administered directly or indirectly to a traumatised vessel.

According to the appellant, the claim's basis is found in claims 1 and 3 and on page 25, line 32 to page 27, line 24 of the application as filed. The board notes that the sole claim of the main request is not the result of a combination of claims as granted and that some features, such as the inhibition of one or more pathological activities or the direct and indirect administration, were not present in the claims as granted. In such a case, according to established case law of the boards of appeal, the opposition division and the board have the power under Article 101(3) EPC to examine whether the amendments introduce any contravention of requirements of the EPC, including Article 84 EPC (G 3/14). This was not disputed.

3.2 Under Article 84 EPC in combination with Rule 43(1) EPC, the claims must be clear and define the matter for which protection is sought in terms of the technical features of the invention. These requirements are there to ensure that the public is not left in any doubt as to what subject-matter is covered and not covered by a claim. Accordingly, a claim cannot be considered clear within the meaning of Article 84 EPC if it does not unambiguously allow this distinction to be made. A claim comprising an unclear or ambiguous technical feature therefore entails doubts as to the subject-matter covered by that claim. This applies all the more if the unclear feature is essential with respect to the invention in the sense that it is intended to delimit the subject-matter claimed from the prior art, thereby giving rise to uncertainty as to whether or not the subject-matter claimed is anticipated (see decision T 560/09, not published, point 2 of the reasons).

3.3 In the case in hand, feature iii) requires the therapeutic agent to be directly or indirectly administered to a traumatised vessel. According to the opposition division and the respondent, the person skilled in the art would construe this feature as clearly referring to the administration of taxol per se to either the point in the vessel where the trauma occurred (direct administration), for example via a stent or an infusion catheter, or a different point from that where the trauma occurred (indirect administration), for example via injection. In the opposition division's and the respondent's view, taxol conjugates, as disclosed in document D2, were therefore clearly excluded from the scope of claim 1 of the main request.

3.4 However, the opposition division's and the respondent's interpretation is not the only way of construing the aforementioned feature. In the board's view, another equally valid and technically feasible understanding of feature iii) is the administration of the therapeutic agent either per se (direct administration) or in a form from which it can be released (indirect administration), such as a conjugate, in which case conjugates would not be excluded from the scope of the claim. It should be noted that the term "indirect administration" was not defined in the application as filed, which drew a distinction between targeted and direct delivery. It is therefore not unreasonable to assume that the expression "indirect administration" was meant to reflect the targeted delivery of the therapeutic agent, as argued by the appellant.

The board therefore does not accept the respondent's arguments that the wording of claim 1 required taxol per se to be administered and that it then followed that feature iii) clearly referred to the point of delivery (see point XVI above). Claim 1 is not directed to a particular final dosage form which is administered to the vessel and which contains the therapeutic agent in a particular, i.e. free, form.

3.5 It follows from the above that feature iii) is not only broad, as argued by the opposition division, but also ambiguous as it can be understood in various ways, i.e. as referring to the point of delivery of the therapeutic agent or to the form in which the therapeutic agent is delivered. This leaves the public in doubt as to what subject-matter is covered and not covered by claim 1 of the main request.

Hence, the board concludes that claim 1 of the main request is not clear within the meaning of Article 84 EPC. The main request is therefore not allowable.